package com.sky.service.impl;

import com.sky.dto.GoodsSalesDTO;
import com.sky.entity.Orders;
import com.sky.mapper.OrderMapper;
import com.sky.mapper.UserMapper;
import com.sky.service.ReportService;
import com.sky.service.WorkspaceService;
import com.sky.vo.*;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;
import org.apache.poi.xssf.usermodel.XSSFRow;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.InputStream;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.LocalTime;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

@Service
@Slf4j
public class ReportServiceImpl implements ReportService {

    @Autowired
    private OrderMapper orderMapper;

    @Autowired
    private UserMapper userMapper;

    @Resource
    private WorkspaceService workspaceService;

    /**
     * 统计指定时间区间内的营业额数据
     * @param begin
     * @param end
     * @return
     */
    @Override
    public TurnoverReportVO getTurnoverStatistics(LocalDate begin, LocalDate end) {

        // 当前集合用于存放从begin到end范围内的每天的日期
        List<LocalDate> dateList = getDateList(begin, end);
        // 日期集合转换为字符串 前端要求的格式
        String dateListString = StringUtils.join(dateList, ",");

        List<Double> turnoverList = new ArrayList<>();     // 存放日期 对应金额
        for (LocalDate date : dateList) {
            // 查询data日期对应的营业额数据
            // 营业额应该是 状态为"已完成"的订单金额合计
            // 获取当天开始时间
            LocalDateTime beginTime = LocalDateTime.of(date, LocalTime.MIN);
            // 获取当天最后时间
            LocalDateTime endTime = LocalDateTime.of(date, LocalTime.MAX);
            // select sum(amount) from orders where order_time > beginTime and order_time < endTime and status = 5
            Map map = new HashMap();
            map.put("begin", beginTime);
            map.put("end", endTime);
            map.put("status", Orders.COMPLETED);
            Double turnover = orderMapper.sumByMap(map);
            // 如果返回的营业额值为 null 将其转换为 数值0.0
            if (turnover == null)
                turnover = 0.0;
            turnoverList.add(turnover);
        }
        String turnoverListString = StringUtils.join(turnoverList, ",");

        // 将数据封装并返回
        return TurnoverReportVO.builder()
                .dateList(dateListString)
                .turnoverList(turnoverListString)
                .build();
    }

    /**
     * 统计指定时间区间内用户数据
     * @param begin
     * @param end
     * @return
     */
    @Override
    public UserReportVO getUserStatistics(LocalDate begin, LocalDate end) {

        // 当前集合用于存放从begin到end范围内的每天的日期
        List<LocalDate> dateList = getDateList(begin, end);
        // 日期集合转换为字符串 前端要求的格式
        String dateListString = StringUtils.join(dateList, ",");

        // 存放每天的新增用户数量
        // select count(id) from user where create_time < ? create_time > ?
        List<Integer> newUserList = new ArrayList<>();
        // 存放每天的总用户数量
        // select count(id) form user where create_time < ?
        List<Integer> totalUserList = new ArrayList<>();
        for (LocalDate date : dateList) {
            LocalDateTime beginTime = LocalDateTime.of(date, LocalTime.MIN);
            LocalDateTime endTime = LocalDateTime.of(date, LocalTime.MAX);

            // 构造查询条件 map
            Map map = new HashMap();
            map.put("end", endTime);
            // 总的用户数量
            Integer totalUser = userMapper.countByMap(map);
            map.put("begin", beginTime);
            // 新增用户数量
            Integer newUser = userMapper.countByMap(map);

            totalUserList.add(totalUser);
            newUserList.add(newUser);
        }

        // 封装结果数据
        return UserReportVO
                .builder()
                .dateList(dateListString)
                .newUserList(StringUtils.join(newUserList, ","))
                .totalUserList(StringUtils.join(totalUserList, ","))
                .build();
    }

    /**
     * 统计指定时间区间内的订单数据
     * @param begin
     * @param end
     * @return
     */
    @Override
    public OrderReportVO getOrdersStatistics(LocalDate begin, LocalDate end) {

        // 当前集合用于存放从begin到end范围内的每天的日期
        List<LocalDate> dateList = getDateList(begin, end);
        // 日期集合转换为字符串 前端要求的格式
        String dateListString = StringUtils.join(dateList, ",");

        // 存放每天订单总数
        List<Integer> orderCountList = new ArrayList<>();
        // 存放每天的有效订单数
        List<Integer> validOrderCountList = new ArrayList<>();

        // 遍历 dateList 集合 查询每天的有效订单数和订单总数
        for (LocalDate date : dateList) {
            // 获取当天最开始的时间
            LocalDateTime beginTime = LocalDateTime.of(date, LocalTime.MIN);
            // 获取当天最后的时间
            LocalDateTime endTime = LocalDateTime.of(date, LocalTime.MAX);

            // 构造查询条件
            Map map = new HashMap();
            map.put("begin", beginTime);
            map.put("end", endTime);
            // 查询每天的订单总数
            // select count(id) from orders where order_time > ? and order_time < ?
            Integer orderCount = orderMapper.countByMap(map);
            // 放入集合
            orderCountList.add(orderCount);

            map.put("status", Orders.COMPLETED);
            // 查询每天的有效订单数
            // select count(id) from orders where order_time > ? and order_time < ? and status = 5
            Integer validOrderCount = orderMapper.countByMap(map);
            // 放入集合
            validOrderCountList.add(validOrderCount);

        }

        // 不将计算总数放入循环中获取原因：降低各代码块之间的耦合度 便于维护

        // 计算时间区间内的订单总数量
        Integer totalOrderCount = orderCountList.stream().reduce(Integer::sum).get();
        // 计算时间区间内的有效订单数
        Integer validOrderCount = validOrderCountList.stream().reduce(Integer::sum).get();


        // 计算订单完成率
        Double orderCompleteRate = 0.0;
        if (totalOrderCount != 0) {     // 避免除0
            orderCompleteRate = validOrderCount.doubleValue() / totalOrderCount;
        }


        return OrderReportVO.builder()
                .dateList(dateListString)
                .orderCountList(StringUtils.join(orderCountList, ","))
                .validOrderCountList(StringUtils.join(validOrderCountList, ","))
                .totalOrderCount(totalOrderCount)
                .validOrderCount(validOrderCount)
                .orderCompletionRate(orderCompleteRate)
                .build();
    }

    /**
     * 获取每天begin到end之间的每天日期集合
     * @param begin
     * @param end
     * @return
     */
    private static List<LocalDate> getDateList(LocalDate begin, LocalDate end) {
        List<LocalDate> dateList = new ArrayList<>();
        // 存放日期
        dateList.add(begin);
        while (!begin.equals(end)) {
            // 计算指定日期的后一天 对应的日期
            begin = begin.plusDays(1);
            dateList.add(begin);
        }
        return dateList;
    }

    /**
     * 统计指定时间区间内的销量排名前10
     * @param begin
     * @param end
     * @return
     */
    @Override
    public SalesTop10ReportVO getSalesTop10(LocalDate begin, LocalDate end) {

        LocalDateTime beginTime = LocalDateTime.of(begin, LocalTime.MIN);
        LocalDateTime endTime = LocalDateTime.of(end, LocalTime.MAX);

        List<GoodsSalesDTO> salesTop10 = orderMapper.getSalesTop10(beginTime, endTime);

        List<String> names = salesTop10.stream().map(GoodsSalesDTO::getName).collect(Collectors.toList());
        String nameList = StringUtils.join(names, ",");

        List<Integer> numbers = salesTop10.stream().map(GoodsSalesDTO::getNumber).collect(Collectors.toList());
        String numberList = StringUtils.join(numbers, ",");

        // 封装返回结果数据
        return SalesTop10ReportVO.builder()
                .nameList(nameList)
                .numberList(numberList)
                .build();
    }

    /**
     * 导处运营数据报表
     * @param response
     */
    @Override
    public void exportBusinessData(HttpServletResponse response) {
        // 1、查询数据库 获取营业数据
        LocalDate dateBegin = LocalDate.now().minusDays(30);
        LocalDate dateEnd = LocalDate.now().minusDays(1);

        // 查询概览数据
        BusinessDataVO businessDataVO = workspaceService.getBusinessData(LocalDateTime.of(dateBegin, LocalTime.MIN), LocalDateTime.of(dateEnd, LocalTime.MAX));

        // 2、通过POI将数据导入到Excel文件
        InputStream in = this.getClass().getClassLoader().getResourceAsStream("template/运营数据报表模板.xlsx");
        try {
            // 基于模板文件 创建新的Excel文件
            XSSFWorkbook excel = new XSSFWorkbook(in);
            // 获得表格文件 sheet 页
            XSSFSheet sheet = excel.getSheet("Sheet1");
            // 填充数据 时间
            sheet.getRow(1).getCell(1).setCellValue("时间：" + dateBegin + "至" + dateEnd);

            // 获取第4行
            XSSFRow row = sheet.getRow(3);
            row.getCell(2).setCellValue(businessDataVO.getTurnover());
            row.getCell(4).setCellValue(businessDataVO.getOrderCompletionRate());
            row.getCell(6).setCellValue(businessDataVO.getNewUsers());

            // 获取第5行
            row = sheet.getRow(4);
            row.getCell(2).setCellValue(businessDataVO.getValidOrderCount());
            row.getCell(4).setCellValue(businessDataVO.getUnitPrice());

            // 填充明细数据
            for (int i = 0; i < 30; ++i) {
                LocalDate date = dateBegin.plusDays(i);
                // 查询某一天的营业数据
                BusinessDataVO businessData = workspaceService.getBusinessData(LocalDateTime.of(date, LocalTime.MIN), LocalDateTime.of(date, LocalTime.MAX));
                // 获得某一行
                row = sheet.getRow(i + 7);
                row.getCell(1).setCellValue(date.toString());
                row.getCell(2).setCellValue(businessData.getTurnover());
                row.getCell(3).setCellValue(businessData.getValidOrderCount());
                row.getCell(4).setCellValue(businessData.getOrderCompletionRate());
                row.getCell(5).setCellValue(businessData.getUnitPrice());
                row.getCell(6).setCellValue(businessData.getNewUsers());
            }

            // 3、通过输出流将Excel文件下载到客户端浏览器
            ServletOutputStream out = response.getOutputStream();
            excel.write(out);

            // 关闭资源
            excel.close();
            out.close();
            // in.close();
        } catch (IOException e) {
            log.error(e.getMessage());
        }

    }

}
